Life cycle assessment of a representative dairy farm with limited irrigation pastures

The environmental impacts and the sustainable development of agricultural activities have been identified as a significant national issue. This paper presents an initial assessment of the life cycle impacts of a representative dairy farm with limited irrigation pastures using SimaPro. The functional unit is defined as the production of one litre of raw milk leaving at the farm gate. The input data is described and the limitation of current investigation is identified. It is shown that for this type of farm, most of the environmental impacts (based on the combined single-score method) are due to the energy use by irrigation pump (33%), the use of the urea fertilizer (27%), and the cow methane emissions (21%). Therefore, future improvements should focus on these three factors. It is also found that the contribution to environmental impact from phosphorous fertilizer, potassium fertilizer, truck and tractor are all relatively small, being 1.22%, 0.11%, 3.47% and 2.24% respectively. In terms of the single-issue indicator of climate change, the contribution from the cow methane emissions is very significant at 76.2%